Drill bit



Oct. 27, 1936. c. F. WILLIAMS ET Al. 2,058,750

DRILL BIT Filed July 16, 1954 2 Sheets-Sheet 1 Jujg. 1.

/ 7 1 3 ATTRNEY C. F. WILLIAMS ET AL.

oct. 27, 1936.

DRILL BIT Filed July 16, 1954 2 Sheets-Sheet 2 Patented Oct. 27, 1936IPATENT OFFICE DRILL BIT Clinton F. Willia Okla., assigne pany, Tonkawa,homa and ,Hans Gruner, Tonkawa, to Williams Iron Works Com- Okla., acorporation o! Okla- Application July 16, 1934, Serial No. 735,340 6Claims. (Cl. 255-71i This invention relates to drill/bits. and moreparticularly to those of rotarytype for use lin drilling earthformations in the making of oil, gas and other wells, and has for itsprincipal objects to provide a bit construction whereby pressure of thedrilling fluid is applied directly to the bottom of the well hole, toprovide a strong rigid mounting of the cutters, to provide a bitlconstruction which effectively drills through rock formations toproduce a straight hole and to provide a bit having extremely longwearing qualities.

In accomplishing these and other objects of the invention we haveprovided improved details of structure the preferred form of which isillustrated in the accompanying drawings wherein:

Fig. 1 is a perspective view of a rotary drill bit embodying thefeatures of the present invention.

Fig. 2 is a vertical section through the bottom of a well hole and drillbit particularly illustrating the construction whereby drilling fluid isdelivered directly to the bottom of the well hole.

Fig. 3 is a similar view showing the bit in three-quarter section asviewed from the side at right angles to the section shown in Fig. 2.

Fig. 4 is an end view of the bit particularly illustrating the relationof the water course extension to the bit cutters.

Fig. 5 is a detail perspective view of the hanger for mounting the crosscutters and the water course extension.

Fig. 6 is `a detail perspective view of one of the side cutter spindles.

Referring more in detail to the drawings:

I designates a rotary drill bit including a head 2 carrying sets of sideand cross roller cutters 3-4 Aand 5-6 respectively. The head 2 includesa substantially disk-shaped body portion 1 having integral side rollersupporting lugs 8 and 9 projecting downwardly from the lower sidethereof at opposite diametrical points and terminating ih spindlesupporting portions I0 and II.

Extending upwardly from the body portion 1 and located in the axis ofthe bit is a tapering pin I2 having external threads I3 for engagingthe4 internal threads I4 of a box joint I5 carried at the lower end ofthe drill pipe as in customary practice. The pin I2 is prov-ided with acentral recess I6 opening rom the upper end 'thereof in direct alignmentwith a water course I1 that extends from the drill pipe through the boxjoint I5 for delivering the drilling uid to the bottom of the well hole.

Extending through the body portion 'l of the drill bit from the bottomof the recess I6 and in a plane passing through the center of thesupporting lugs 8 and 9 are outlet ports I8 for directing jets ofdrilling iluid directly onto the 5 teeth of the side cutters 3-4 now tobe described.

The side cutters 3-4 include substantially truncated cone-shaped bodyportions I9 having peripheral cutting teeth 20 for making a circular 10cut upon rotation of the bit as later described. The body portion I9 ofthe cutters have axial openings 2| for mounting sets of roller bearingstherein, and which operate on the spindles 23 to provide free rotationof the cutters about l5 the bottom of the Well hole upon rotation of thebit. The spindles 23 include head flanges 24 of larger dlameterthan theaxial openings 2| to engage in circular recesses 25 that are formed inthe inner face of the cutters as best illus- 20 trated in Fig. 3, and tocooperate with outwardly and downwardly inclined inner faces 26 of thelugs- 8 and 9 to retain the cutters on the spindles. The inner and outerfaces of the cutters are preferably provided with anti-friction 25bearings 2l and 28 adapted to engage against the flanges 24 and againstthrust washers' 29 that are seated against the inner face of the lugs 9and 9. The spindles 23 have reduced shanks 30 to form stop shoulders 3Ifor engaging 30 against the thrust washers 29 to preventbinding of thecutters between the head flanges 24 and the thrust washers when theshanks 30 are welded into openings 32 that are formed in the lugs 8 and9. The inclination of the 35 faces 26 on the lugs 8 and 9 and the axesof the openings 32 are arranged relative to the axis of the bit so thatthe cutting edges of the teeth 2li form a downwardly tapering Acircularcut defining the outer diameter of the hole be- 40 ing drilled, asillustrated at 33, Figs. 2 and 3.

In the illustrated instance, the cross cutters are of cylindrical shapeand have teeth 34 extending in angular relation to their axis ofrotation, which is arranged in a horizontal plane at right 45 angles tothe plane of the axes of the side cutters in such a manner that thecross cutters engage the bottom of the well hole to make a circular cutin the formation overlapping with the cut 33.

In order to apply pressure of the drilling uid 50 directly on the bottomof the well hole, the water course as formed by the recess I6 isextendeddownwardly by means of an extension pipe 35f. having its upper endwelded in an opening 36 offset from the axis of the body substantially55.

equal to the radius of the pipe. and which communicates with the recessI6. of the pipe terminates short of the bottom of the well hole toprovide outlet for the drilling fluid which moves therethrough underpressure against ,the bottom of the well hole and is diverted outwardlytoward and between the teeth of the respective cutters from where itcirculates upwardly through the well hole for return to the surface.

Extending between the head flanges 24 of the spindles 23 is a hangermember 38 including a substantially rectangular-shaped block 39 havingtriangular-shaped lugs 40 and 4| extending from the ends thereof, andhaving inclined faces 42 conforming to the angle of which are weldedthereto, as indicated at 43. 'I'he hanger thus forms a brace between thespindles to cooperate with ears 44 and 45 which depend from the body 1midway between the lugs 8 and 9 in rotatably mounting the side cutters.'I'he block portion 39 of the hanger has a vertical elongated slot 46through which the lower end of the water course pipe 35 is extended, asshown in Figs. 2 and 3, the pipe being welded to the inner walls of theslot as indicated at 41.

Extending outwardly from openings 48 and 48" in the side faces 48 of theblock portion 39 on its sides opposite to the lugs 40 and 4| arelaterally extending pins 49 and 50 for rotatably mounting the crosscutters 5 6 and which have their outer ends mounted in the ears 44 and45. 'I'he hanger is mounted in offset relation to the axis of the bit,as shown in Fig. 4, to accommodate an intermediate cross cutter 5|,preferably of slightly smaller diameter than the cross cutters 5 6, andwhich produces an inner circular cut at slightly higher elevation thanthat made by the cutters 5 6. The pin 59 is therefore longer than thepin 49 to accommodate the intermediate cutter 5|. The intermediatecutter 5| is preferably of sufllcient width to almost complete the spaceacross the diameter of the hole when the bit is rotated. However, thecenter of the well hole not engaged by the cutters is suillciently smallthat it is readily chipped off during operation of the blt.

'I'he cross cutter 5, when sleeved on the pin 49 and the intermediatecutter 5| when sleeved on the pin 50, have the inner side faces 52 and53 thereof bearing against thrust washers 54 and 55 which, in turn,engage against the side faces of the hanger member. The opposite crosscutter 6, which is mounted on the same pin as the intermediate cutter5|, is spaced from the intermediate cutter by a washer 56, as shown inFig. 2. 'I'he cross cutters, when mounted on the pins 49 and 50, areretained by the ears 44 and 45 which have openings 51 and 58 to receivethe projecting ends of the pins and in which the pins are welded, asshown in Fig. 2. The cross cutters thus described may also carry rollerbearing sets 59 similar to the bearing sets for mounting the sidecutters previously described.

In assembling the bit constructed as described the side rollers 3 4 aremounted on the bearing portions of the spindles 23 so that the headflanges 24 thereof enter the recesses in the inner faces of the sidecutters. The shanks of the spindles are then driven into the openings 32formed in the lugs 8 and 9, after which the ends of the shanks arewelded to the lugs shown at 60, in Fig. 3. One of the pins 49 and 50,for example the pin 49, is then welded in the opening 48 of the blockportion 39 of the hanger.

'Ihe lower end 31" ing 51 for'welding to the the spindle heads, and

8 and 9, as`

The cross cutter 5 is sleeved thereon and the outer projecting end ofthe pin is inserted in the opencross cutter 6 and intermediate cutter 5|are placed in axial alignment with the openings43" in the member 39 and58.in the ear 45 whereupon the pin 50 is inserted therethrough andwelded to the member 39 through the slot 46 and to the ear as at 6|.'I'he water course extension pipe 35 is then projected through theslotted opening 46 and welded to the inner walls thereof, as shown inFig. 5 after its upper end has been welded into the opening 36. Thehanger including the water course extension pipe has now been applied tothe bit and the lugs 40 and 4| of the hanger are bearing against thehead flanges of the spindles to be welded thereto as shown at 43.

When the bit is thus assembled and lowered into the well, the drillingfluid delivered through the water course i1 will flow through theextension pipe 35 directly against the formation being drilled to washthe cuttings outwardly from the bottom of the bit for flow upwardlybetween the wall of the well and the drill pipe.

Upon rotation of the bit the teeth of the cutters roll over theformation on which the bit is supported, and as pressure is applied theteeth are caused to cut into and chip out sections of the formationwhich are washed away by the drilling fluid flowing between the teeth.During rotation of the bit the jet of drilling fluid discharged throughthe pipe 35 will gyrate about the axis of the well hole and over a smallportion of the formation which is not directly acted upon by the teethoi the cutters but, as above mentioned, the intermediate cutter islocated sufficiently close to the center to cause breaking oil of thispart of the formation.

From the foregoing it is apparent that drilling fluid is delivered underpressure directly to the bottom of the well hole to keep the bottomformation entirely free of cuttings and other obstructions that mayinterfere with the cutting action of the teeth.

It is also apparent that the hanger provides a rigid mounting for thecross cutters, 'and also braces the lugs 9 and 9 carrying the side.cutters, thereby providing stronger bit construction.

What we claim and desire to secure by Letters Patent is:

1. A drill bit including a bit head having a Water course, spindlesmounted on the bit head, side cutters rotatably mounted on the spindles,a hanger member offset from axes of the side cutters and secured to thespindles, stub shafts having ends fixed to opposite sides of the hangermembermeans on the bit head mounting the opposite ends of the stubshafts, cross cutters rotatably mounted on the `ub shafts, and meansextending from said water course through said hanger member and havingan unobstructed inner bore for delivering well fluid in jet formationagainst the bottom of a well hole drilled by the '2. A drill bit,including a bit head having a Water course, spindles mounted on the bithead, side cutters on the spindles, a hanger member offset from axes ofthe side cutters and secured to the spindles, stub shafts having spacedends fixed to the hanger member, means on the bit head mounting oppositeends of the stub shafts, cross cutters rotatably mounted on the stubshafts, a pipe having one end connected with the water course and itsopposite end extending through the ear u as at en'. The

hanger member between said spaced ends of the stub shafts fordischarging a jet of drilling uid from said water course directlyagainst the bottom of a well hole drilled by the bit.

3. A drill bit including a bit head, having a water course, spindlesmounted on the bit head, side cutters on the spindles, a hanger memberhaving lugs connected with the spindles and having a vertical openingoiset from axes of the side cutters, stub shafts having spaced ends xedto said hanger member at opposite sides of said opening, cross cuttersrotatably mounted on the stub shafts, and a pipe connected with thewater course and extending through said opening between the spaced endsof said stub shafts and having an unobstructed bore terminating in closeproximity to the bottom of the well hole drilled by the bit fordelivering drilling luid from said water course in jet formationdirectly against the bottom of the well hole.

4. A drill bit including a bit head, having a. water course, a hangermember on the bit head having a vertical opening therethorugh, stubshafts having spaced ends fixed to said hanger member at opposite sidesof the opening, cross cutters rotatably mounted on the stub shafts, anda pipe connected with the water course and cxtending through saidopening between the spaced ends of said stub shafts and having anunobstructed bore terminating in close proximity to the bottom of thewell hole drilled by the bit for delivering drilling fluid from saidwater course in jet formation directly against the bottom of the wellhole.

5. A drill bit including a bit head having a wa.- ter course, a hangermember having an opening oiset from the axis of rotation of the bit,stub shafts having spaced aligning ends fixed to the hanger member atopposite sides of said opening, means on the bit head mounting theopposite ends of the stub shafts, cross cutters rotatably mounted on thestub shafts, and a pipe extending from said Water course through theopening between said spaced ends of the stub shafts and having anunobstructed inner bore for delivering well fluid in jet formationagainst the bottom of a well hole drilled by the bit.

6. A drill bit including a bit head having a water course, spindlesmounted on the bit head, toothed side cutters on the spindles, a hangermember oiset from axes of the side cutters and secured to the spindles,stub shafts having spaced 20

